st: Data Management

Hi statalist,
I have a data set as follows
ID City Year
1 City name 1
1 City name 2
The data is suppose to have same city names for each ids for year 1
and two. but there are many occasions where city for the year 1 is
spelt differently thanthat for year 2. I just want to list out or edit
those cities where city names are different for year 1 and 2 for the
same ID. When I issue the following command
bysort ID : list if City!=City[_n-1]
it lists all observations in the data whether or not the city is spelt
differently in years one and two. Thats strange to me? Can someone
tell what I am doing wrong here?
Thanks for your help.
Rijo.
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